Diquaternary ammonium compounds and the manufacture thereof



United States Patent DIQUATERNARY AMMONIUM COMPOUNDS AND THE MANUFACTURE THEREOF Albert Gordon Caldwell, London, England, assignor to Burroughs Wellcome & "C0. (U.S.A.) Inc., Tuckahoe, N.Y., a corporation of New York No Drawing. Application April 3, 1957 Serial No. 650,288

Claims priority, application Great Britain April 6, 1956 1 Claim. (Cl. 260-243) The'present invention relates to novel diquaternary compounds and to their manufacture.

It has been found that compounds falling within the general Formula I have the property of blocking ganglion transmission when tested in experimental animals, for

example, the cat.

in this formula, R and R 'are either each a ,phenyl group or they together formwith the neighbouring nitrogen'atom a carbazole, a phenoxazine or a phenothiazine ring system or the sulphoxide or the sulphone of a phenothiazine ring system; nis aninteger from two to ten;

is a quaternary'nitrogen atom carrying two alkyl groups which may be methyl or ethyl groups;

is a quaternary nitrogen atom carrying 'at least one methyl or ethyl group and either carrying two further alkyl groups, which may be methyl or ethyl groups, or

forming part of a pyrrolidine, piperidine or morpholine ring; Y is an alkylene'chainhaving two or three carbon atoms; and A- is an anion of an inorganic or organic acid which may be, for example, halide 'or'alkyl sulphate.

These compounds possess extremely powerful pharmacological properties resembling, but in many ways considerably greater than those of known ganglion blocking agents such as 'hexameth'onium and pentolinium. 'Thus, when injected into cats and dogs they lower the "blood pressure and block the hypertensive action of the ganglion stimulating substance DMPP (N :'N

peristaltic reflex of the isolated guinea-pig ileum but are only weak antagonists of locally applied acetyl'choline. The intensity of thevarious autonomie actions of the 'examples described in this application varies with the chemicalconstitution of the"example, the nature of the action and the animal-speciesin which the action is meassured. "Many of the compounds described are considerably more :active thanknown ganglion blocking'agents such as hexamethonium and pentolinium in inhibiting 'DMPP hypertension :and preventing vagal bradycardia in cats, and have the additional advanta'geof a much longer -duration :of action.

lower dialkyl sulphate.

In this formula R R Y-and n have the meanings given above, N is a secondary, tertiary or quaternary nitrogen atom and N is .a primary, tertiary or quaternary nitrogen atom, the substituents provided by the quaternising agent, together with any substituentson N and N being such as will give the desired substitution in the compound of general Formula I.

Thus, for example, N may be a tertiary nitrogen atom carrying one methyl or ethyl-group and N may be a tertiary nitrogen atom carryingtwo alkyl groups which may be methyl or ethyl groups or may form part of a ,pyrrolidine, piperidine or morpholine ring.

The'quaternisation reaction may be carried outby allowing the amine to stand with or by heating it with a quaternising agent such as a lower alkyl halide, in a suitable solvent such as acetone or methanol with the addition where necessary of an acidbinding agent, for example, sodium carbonate.

Compounds of the 'Formula II where N is a secondary or a tertiary nitrogen atom and N is a tertiary nitrogen atom may be synthesised by the following routes.

A sodio compound of the Formula III is reacted with apolymethylene-otzw-dihalide of the Formula'IV, Where n'has the meaning given above and where Z and Z are suitable different halogen atoms, for example,.iodine. and

chlorine atoms respectively, in a suitable solvent, for example, liquid ammonia, to (give a compound of the "atom, in a suitablesolvent, for example, ethanol, to give the required compound of Formula II.

'Where the groups R and R in the compound of Formula II together form with the neighbouring nitrogen atom the sulphoxide or the sulphone of aphenothiazine ring system, the compound of Formula V is oxidised,by means of hydrogen peroxide in ethanol, for example, to give the correspondingsulphoxide of Formula VII .or, by means 'of hydrogen peroxide in glacial acetic acid,

and stirring was continued for 1 hour.

for example, to give the corresponding sulphone of Formula VIII.

(VIII) :erally the iodide is an easily crystallisable salt. However,

the methods described are also applicable to the preparation of other salts; Also, the iodide may be converted into other salts; treatment with silver chloride, for example, gives the chloride, and contact with a suitable ion exchange resin gives the hydroxide, which may be con verted into any desired salt.

Example 1 7 Liquid ammonia (600 ml.), contained in a flask surrounded by a cooling bath, was stirred, and a few small pieces of sodium were added, followed by a crystal of ferric nitrate. When the blue solution had become colourless, more sodium (total 7.8 g.) was added in pieces Diphenylamine (50.7 g.) was added to the cooled mixture over about 20 minutes and stirring was continued for a further 1 hour. 1-chloro-4-iodobutane (65.5 g.) was added dropwise over minutes and the mixture was stirred in the cooling bath for another 1 hour, after which the cooling bath was removed, and the ammonia allowed to evaporate overnight at room temperature. The dark residue 'was extracted with hot light petroleum (boiling point 6080), the solvent was evaporated, and the residual oil was distilled, to give N-(4-chlorobutyl)diphenylamine, boiling point 124128/0.05 mm. (Benoit, Delavigne and Eliopoulo, Chemical Abstracts, 1953, 47, 2148e, give a boiling point of 2l0211/16 mm.).

A solution of N-(4-chlorobutyl)diphenylamine (7.8 g.) and fl-piperidinoethylmethylamine (8.5 g.) in ethanol (25 ml.) was refluxed for 6 hours. The solution was evaporated to dryness and the residue was treated with excess dilute hydrochloric acid. The solution was washed with chloroform and then made alkaline with sodium hydroxide solution, and the precipitated oil was extracted with chloroform. The dried extract was evaporated, and the residue was distilled to yield N-l4-(p-piperidinoethylmethylamino)butylJdiphenylamine, boiling point 168- 170/0.01 mm.

The dihydrochloride, prepared by the addition of ethereal hydrogen chloride to a solution of the base in iso- 4 ride, melting point 221-223"; dimethiodide, melting point 192-l 94 N- [4 13-diethylaminoethylmethylamino)butyl]diphenylamine, boiling point 167170/ 0.04 mm.; (dimethiodide, melting point -118).

N-[4-( 3 pyrrolidinoethylmethylamino)butylldiphenylamine, boiling point 174l81/ 0.04 mm. (dihydrochlon'de, melting point 221-223; dimethiodide, melting point 186-188 Example 2 Using sodamide in liquid ammonia as described in Example 1, diphenylamine and l-chloro-S-iodopentane were condensed together to give N-(5-chloropentyl)diphenylamine, boiling point 136-137/0.01 mm. (Benoit, Delavigne and Eliopoulo, Chemical Abstracts, 1953, 47, 2148e, give a boiling point of 220-223/20 mm.)

N-(S-chloropentyl)diphenylamine reacted with ti-piperidinoethylmethylamine under the conditions described in Example 1 to give N-[S-(B-piperidinoethylmethylamino)- pentyl]diphenylamine, boiling point 188190/ 0.01 mm. By the methods of Example 1, this base was converted to its dihydrochloride, melting point 207-209 and its dimethiodide, melting point 207-209 (with efierverscence).

Similarly, the following compounds were prepared:

N-[S (B diethylaminoethylmethylamino)penty11diphenylamine, boiling point l70173/0.01 mm. (dimethiodide, melting point 217' (with etiervescence.))

N- [5- fi-morpholinoethylmethylamino) pentyl] diphenylamine, boiling point'192-198/0.01 mm. (dihydrochloride, melting point 200-202"; dimethiodide, melting point 206 (with effervescence.))

N-[S-(p pyrrolidinoethylmethylamino) pentyl1diphenylamine, boiling point 179186/0.05 mm. (dimethiodide, melting point 225 (with efi'ervescence)).

Example 3 By the procedure described inExample 1, N-(9-chlorononyl)diphenylamine, boiling point -172/ 0.01 mm., was prepared from diphenylamine and 1-chloro-9-iodononane. N-(9-chlorononyl)-diphenylamine and fi-piperidinoethylmethylamine reacted together under the conditions described in Example 1 to give N-[9-(fi-piperidinoethylmethylamino)nonyl]diphenylamine, which was isolated as its dihydrochloride, melting point 235, with decomposition.

The base, treated with methyl iodide as in Example 1, gage N- 9- p-piperidinoethylmethylamino) nonyl] diphenylamine dimethiodide as plates, melting point 190-192, after crystallisation from isopropanol.

Example 4 To a suspension of sodamide in liquid ammonia (pre pared from sodium (2.6 g.) as described in Example 1) was added carbazole (16.7 g.) over 20 minutes. After stirring for 1 hour, l-chloro-S-iodopentane (25.6 g.) was added over 45 minutes, and the mixture was cooled and stirred for a further 1 hour. The cooling bath was removed, and ammonia was allowed to evaporate overnight at room temperature. Water was added to the residue and the insoluble solid was collected and washed with water. Recrystallisation from methanol gave 9-(5-ch1oropentyl)carbazole as colourless needles with a blue fluorescence, melting point 60-61.

The foregoing chloro-compound and ,B-piperidinoethyh methylamine reacted under the conditions described in Example 1 to give 9-[5-(fi-piperidinoethylmethylamino)- pentylkarbazole as a viscous oil with a blue fluorescence, boiling point 2l7-219/0.01 mm. The dihydrochloride of the base formed colourless prisms, melting point 226- 230. The dimethiodide of the base was obtained, by the method of Example 1, as a light brown powder of low and indefinite melting point.

Th? l QHQ ing compounds were prepared similarly 5 from 9-.(5-chloropentyl) carbazole and the appropriate diamtne:

9- [5--pyrrolidinoethylmethylamino pentyl] carbazole, boiling point 2l0214/0.02. mm. (dimethiodide, solid of low and indefinite melting point).

9-[5 (,3 morpholinoethylmethylamino)pentyl]carbazole, boiling point 2l42.16/ 0.02 mm. (dimethiodide, melting point 196-198 with effervescence).

Example 5 To a suspension of sodamide in liquid ammonia (prepared from sodium (2.6 g.) as. described in Example 1), was added phenothiazine (19.9 g.) in portions over 20 minutes, and the mixture was stirred for 1 hour. l-bromo- 3.-chloropropane (17.3 g.) was; added dropwise over 30 minutes, and the stirring was continued for a further 1 hour, after whichv the cooling: bath was removed, and the ammonia was. left. to evaporate at: room temperature. The residue was extracted with; hot light petroleum (boiling point 60-80") and the extract was evaporated. to leave a purple oil. This was dissolved in methanol, and the solution was treated with charcoal and allowed to crystallise, yielding large prisms of 10-(3-chloropropyl)- phenothiazine, melting point 6769 (Gilman and Shirley, J. Amer. Chem. Soc. 1944, 66, 888 give a melting point of 60).

A solution of 10-(3-chloropropy1)phenothiazine (13.4 g.) in a mixture of ethanol (50 ml.) and benzene ml.) was added dropwise. over. 3 hours to a. refluxing solution of B-diethylaminoethylamine (11.6 g.) in ethanol (10 ml.) and the solution wasboiled for a further 21 hours. The basic product, was. worked up into chloroform, and distilled, giving 10-[3-(B-diethylaminoethylamino)propyl]- phenothiazine as a viscous oil, boiling point 192l94/ 0.01 mm. The dihydrochloride crystallised from a mixture of isopropanol and light petroleum (boiling point 60-80") as shining plates, melting point 148-150.

The above base (4.5 g.) was dissolved in methanol (22.5 ml.), anhydrous sodium carbonate (7.5 g.) and methyl iodide (7.5 ml.) were added, and the mixture was refluxed for 5 /2. hours. The cooled mixture was filtered, and the filtrate was evapo-ratedto dryness. The residue was dissolved in hot ethanol, the solution depositing a gum on cooling. The liquid was decanted, and the gum was rubbed with isopropanol to give a colourless solid which was a hydrate of 10-[3-(B-diethy1aminoethylmethylamino) propyl] phenothiazine dimethiodide. It softened at 75 80 and melted with eitervescence at about 100".

Example 6 Using the same conditions as described in Example 5, sodiophenothiazine was treated with 1-bromo-4-chlorobutane, and the product was distilled to give 10-(4-chlorobutyl)phenothiazine as a pale yellow oil, boiling point l64166/0.01 mm. (Robinson and Cusic, US. patent specification No. 2,590,125 give a boiling point of 205- 210/1m m.).

A solution of this chloro-compound (13.5 g.) and 'yatminopropylmor-pholine (13.5 g.) in ethanol (30 ml.) was refluxed for 24 hours. The basic product was distilled to give 10-[4-('y-morpholinopropylamino)butyl]- phenothiazine as a viscous oil, boiling point 230 234/ 0.01 mm. The dihydrochloride of this base crystallised from slightly aqueous isopropanol as colourless needles, melting point 218220.

10 [4 ('y morpholinopropylamino)butyllphenothiazine (5 g.) was treated with methyl iodide (10 ml.) in the presence of sodium carbonate (10 g.), as described in Example 5, to give l0-[4-(' -morpholinoprop-ylmethylamino)butyllphenothiazine dimethiodide. This salt, on recrystallisation from ethanol, was deposited as a guru which slowly solidified and had a melting point of 95-105 Example 7'.

A solution of 10-(4-chlorobutyhphenotliiazine (8 .71.) and B-morpholinoethylmethylamine- ('11 g.) in ethanol (20 ml.) was boiled under reflux for IZG-hou-rs. The soIution was evaporated to dryness under diminished pressure and the residue was treated with excess dilute hydrochloric acid. The aqueous solution was washed with chloroform and then basified with sodium hydroxide solu tion. The precipitated oil was extracted withchl'oroform; and the extract was washed with water, dried; and evaporated to remove the chloroform. The dark residue was dissolved inethanol, and excess of an ethanolic solution of oxalic acid was added; The precipitated solid was just dissolved by the gradual addition of" water tot'he hot suspension, and the solution was allowedto cool. The solid which crystallised was recrystallised from waterto give small plates, melting point 208 (with effervescence); of 10-[4-(5 -'morpholinoethylmethy1amino )butyl'Tphenothiazine di'(hydrogen oxalate).

The oxalate was suspended in water' and sodium hydroxide solution was added to precipitate the base, which was extracted with chloroform. The oil remaining after evaporation of thewashed and dried extract was boiled with methyl iodide in methanol asdescribed in Example 1, to give 10-l4-(B-morpholinoethylmethylamino)butyl] phenothiazine dimethiodide' as smallplates, melting point 210 (with efiervescence) after crystallisation from methanol.

Example 8 The reaction of sodiophenothiazine with. 1-chloro.-5- iodopentane under the conditions described in Example 5 gave 10-(5-chloropentyl)phenothiazine as a viscous pale yellow oil, boiling point 172-174:/0.01 mm. A solution of this chloro'compound' (10.1 g.) and B-piperidinoethylmethylamine (9.5 g.) in ethanol. (20 ml.) was boiled for 5% hours. The basic product. was worked. up into chloroform and distilled to give l0-[S-(fi piperidinQethYI methylamino)pentylJphenothiazine as a viscous yellow oil", boiling point 213218/0'.01 mm. The di(hydrogen oxalate) of this base, prepared by treating a solution of the base in ethanol with excess ethanolic oxalicacid, crystallised from water as small colourless plates,- melting point 195498". pentyllphenothiazine dimethiodide, prepared by treating the base with methyl iodide as described in Example, I, had a melting point of147-150 after crystallisation from ethanol.

Example 9-" To a suspension of 10-(5-chloropentyl)phenothiazine (2 g.) in ethanol (20 ml.) was added hydrogen peroxide (5 ml. of 30%) and the mixture was boiled for 5 hours. The reaction mixture was evaporated to small volume, water was added, and the precipitated oil was extracted with chloroform. The washed and dried extract was evaporated to leave an oil which solidified when rubbed under light petroleum (boiling point 60-80 Recrystallisation from cyclohexane (charcoal) gave colourless plates, melting point 111, of 10-(S-chloropentyl)phenothiazine- 5-oxide.

Reaction of the foregoing ,chloro-compound with B- morpholinoethylmethylamine, followed by treatment of the crude product with oxalic acid, as described in Example 7, gave 10-l5-(fl-morpholinoethylmethylamino)- pentyl]phenothiazine-S-oxide di(hydrogen oxalate) as,

plates, melting point 215 (with etfervescence), from Water.

The oxalate was converted to the base, and this was treated with methyl iodide, as described in Example 7, i

10- [5 B-piperidinoethylmethylamino 7 Example 10 A solution of l-(5-chloropentyl)phenothiazine (2 g.) in glacial acetic acid(l0 ml.) was shaken at room temperature during the addition of hydrogen peroxide ml. of 30%), after which the whole was heated on the steam-bath for 3 hours. Water was added to the hot solution until solid just appeared, and the mixture was left to cool. The solid which crystallised was recrystallised from methanol to give colourless plates, melting point Ill-113, of -(5-ch1oropenty1)phenothiazine- 5'z5-dioxide. The reaction of the foregoing chloro-compound with p-morpholinoethylmethylamine, and the isolation of the product as oxalate, were conducted as described in Example 7, to give 10-[5-(B-morpholinoethylmethylamino) pentyl] phenothiazine-S S-dioxide di(hydrogen oxalate) melting point 218 (with efiervescence). By the method of Example 7, this oxalate was converted to 10-[5-(,6-morpholinoethylmethylamino)pentyl] phenothiazine-S:S-dioxide dimethiodide, melting point 225 (with effervescence). In exactly similar fashion, l0l5-(fi-piperidinoethylmethylamino) pentyl] phenothiazine-S S-dioxide di (hydrogen oxalate), melting point 214 (with effervescence), was prepared and converted into the corresponding dimethiodide, melting point 220 (with elfervescence).

Example 11 A suspension of sodamide in liquid ammonia (ca. 200 ml.) was prepared from sodium (900 mg.) as described in Example 1. Phenoxazine (6.3 g.) was added over 20 minutes and after'stirring for 1 hour, 1-chloro-5-iodopentane (9 g.) was added dropwise over 1 hour. The cooling bath was removed and the ammonia was allowed to evaporate. The residue was extracted with hot light petroleum (boiling point 60-80), the solvent was evaporated and the residue was distilled. The oil which was collected at 170190/0.02 mm. soon solidified and was recrystallised from light petroleum (boiling point 40- 60), with charcoal, to give colourless prismatic needles, melting point 57-5 8", of 10-(5-chloropentyl)phenoxazine. A solution of this chloro-compound (3.5 g.) and fi-morpholinoethylmethylamine (4 g.) in alcohol (10 ml.) was boiled for 6 hours. The crude basic portion was isolated in the normal fashion as a dark oil, which was dissolved in ethanol and treated with excess ethanolic 'oxalic acid to yield 10-[5-(fi-morpholinoethylmethylamino)pentylJphenoxazine di(hydrogen oxalate), which crystallised from water as small colourless plates, melting point 200", with efiervescence. 10-[5-(fi-morpholinoethylmethylamino)pentyl]phenoxazine (1.9 g.), obtained I claim: Compounds of the general Formula I N "'(CH2)nN Y-"N 2A- (I) wherein R and R are radicals selected from the class consisting of phenyl groups and radicals which with the neighbouring nitrogen atom form a group selected from the class consisting of carbazole, phenoxazine, phenothiazine, sulphoxide of phenothiazine and sulphone of 'phenothiazine groups; n is an integer from two of ten;

is a quaternary nitrogen atom having two alkyl groups connected therewith selected from the class consisting of methyl and ethyl groups;

is a quaternary nitrogen atom selected from the class consisting of quaternary nitrogen atoms connected with one alkyl group selected from the class consisting of methyl and ethyl groups and forming a group selected from the class consisting of pyrrolidine, piperidine and moropholine groups and quaternary nitrogen atoms carrying three alkyl groups selected from the class consisting of methyl and ethyl groups; Y is an alkylene chain having the number of carbon atoms selected from the class consisting of two carbon atoms and three carbon atoms; and A" is the anion of a therapeutically acceptable acid.

References Cited in the file of this patent UNITED STATES PATENTS 2,480,355 Charpentier Aug. 30, 1949 2,758,114 Miescher Aug. 7, 1956 2,783,237 Cavallito et al. Feb. 26, 1957 FOREIGN PATENTS 168,173 Australia June 10, 1954 1,021,280 France Nov. 26, 1952 756,937 Great Britain Sept. 12, 1956 

